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A Possible γ-Ray Pulsation from PSR J1740-5340B in the Globular Cluster NGC 6397

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Research in Astronomy and Astrophysics 2024年第1期24卷 285-291页

作者： jiao Zheng Pengfei zhang Li zhang Department of Astronomy School of Physics and AstronomyKey Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China

Recently, a new radio millisecond pulsar(MSP) J1740-5340B, hosted in the globular cluster(GC) NGC 6397,was reported with a 5.78 ms spin period in an eclipsing binary system with a 1.97 days orbital period. Based on a modified radio ephemeris updated by tool tempo2, we analyze the ~15 yr γ-ray data obtained from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope and detect PSR J1740-5340B's γ-ray pulsation at a confidence level of ~4σ with a weighted H-test value of ~26. By performing a phase-resolved analysis, the γ-ray luminosity in on-pulse interval of PSR J1740-5340B is L_(γ)~ 3.8 × 10^(33) erg s^(-1) using NGC 6397's distance of 2.48 kpc. And γ-rays from the on-pulse part of PSR J1740-5340B contribute ~90% of the total observed γ-ray emissions from NGC 6397. No significant γ-ray pulsation of another MSP J1740-5340A in the GC is detected.Considering that the previous four cases of MSPs in GCs, more data in γ-ray, X-ray, and radio are encouraged to finally confirm the γ-ray emissions from MSP J1740-5340B, especially starving for a precise ephemeris.

关键词： gamma-rays:galaxies (stars:)pulsars:individual(PSR J1740-5340B) (Galaxy:)globular clusters:individual(NGC 6397)

Clinical and molecular characterization of 10 Chinese children with congenital adrenal hyperplasia due to 11beta‑hydroxylase deficiency

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World Journal of Pediatrics 2024年第4期20卷 422-433页

作者： Wen‑Li Lu Xiao‑Yu Ma jiao zhang Jun‑Qi Wang Ting‑Ting zhang Lei Ye Yuan Xiao Zhi‑Ya Dong Wei Wang Shou‑Yue Sun Chuan‑Yin Li Rong‑gui Hu Guang Ning Li‑Dan zhang Department of Pediatrics Ruijin HospitalShanghai Jiao Tong University School of MedicineNo.197Ruijin 2nd RdHuangpu DistrictShanghai 200025China Department of Pediatric Genetic and Metabolic Endocrinology West China Second University HospitalSichuan UniversityNo.20Section 3Renmin South RoadSichuan 610041China Department of Endocrine and Metabolic Diseases Shanghai Clinical Center for Endocrine and Metabolic DiseasesRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Cancer Center School of MedicineShanghai Tenth People’s HospitalTongji UniversityYanchang Zhong Lu 301St RdJing’an DistrictShanghai 200031China

Background The clinical manifestations of nonclassical 11beta-hydroxylase deficiency are very similar to those of nonclassical 21-hydroxylase deficiency.For this study,we investigated the relationship between the clinical and molecular features of congenital adrenal hyperplasia caused by 11beta-hydroxylase deficiency and reviewed the related literature,which are expected to provide assistance for the clinical diagnosis and analysis of congenital adrenal hyperplasia.Methods Clinical data for 10 Chinese patients diagnosed with congenital adrenal hyperplasia in our hospital from 2018 to 2022 were retrospectively analyzed.We examined the effects of gene mutations on protease activity and constructed threedimensional structure prediction models of proteins.Results We describe 10 patients with 11beta-hydroxylase gene mutations(n=5,46,XY;n=5,46,XX),with 10 novel mutations were reported.Female patients received treatment at an early stage,with an average age of 2.08±1.66 years,whereas male patients received treatment significantly later,at an average age of 9.77±3.62 years.The most common CYP11B1 pathogenic variant in the Chinese population was found to be c.1360C>T.All mutations lead to spatial conformational changes that affect protein stability.Conclusions Our study found that there was no significant correlation between each specific mutation and the severity of clinical manifestations.Different patients with the same gene pathogenic variant may have mild or severe clinical manifestations.The correlation between genotype and phenotype needs further study.Three-dimensional protein simulations may provide additional support for the physiopathological mechanism of genetic mutations.

关键词： 11β-hydroxylase deficiency CYP11B1 Enzymatic activity Phenotype-genotype correlation Threedimensional protein simulations

A Provable Positivity-Preserving Local Discontinuous Galerkin Method for the Viscous and Resistive MHD Equations

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Communications on Applied Mathematics and Computation 2024年第1期6卷 279-310页

作者： Mengjiao jiao Yan Jiang Mengping zhang School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026AnhuiChina

In this paper,we construct a high-order discontinuous Galerkin(DG)method which can preserve the positivity of the density and the pressure for the viscous and resistive magnetohydrodynamics(VRMHD).To control the divergence error in the magnetic field,both the local divergence-free basis and the Godunov source term would be employed for the multi-dimensional VRMHD.Rigorous theoretical analyses are presented for one-dimensional and multi-dimensional DG schemes,respectively,showing that the scheme can maintain the positivity-preserving(PP)property under some CFL conditions when combined with the strong-stability-preserving time discretization.Then,general frameworks are established to construct the PP limiter for arbitrary order of accuracy DG schemes.Numerical tests demonstrate the effectiveness of the proposed schemes.

关键词： Viscous and resistive MHD equations Positivity-preserving Discontinuous Galerkin(DG)method High order accuracy

Neighbor Sum Distinguishing Total Choosability of Planar Graphs with Maximum Degree at Least 10

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 211-224页

作者： Dong-han zhang You Lu Sheng-gui zhang Li zhang School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an710129China School of Mathematics and Computer Application Shangluo UniversityShangluo726000China

A neighbor sum distinguishing(NSD)total coloringφof G is a proper total coloring of G such thatΣz∈EG(u)U{u}φ(z)≠Σz∈EG(v)U{v}φ(z)for each edge uv∈E(G),where EG(u)is the set of edges incident with a vertex u.In 2015,Pilśniak and Wozniak conjectured that every graph with maximum degreeΔhas an NSD total(Δ+3)-coloring.Recently,Yang et al.proved that the conjecture holds for planar graphs withΔ≥10,and Qu et al.proved that the list version of the conjecture also holds for planar graphs withΔ≥13.In this paper,we improve their results and prove that the list version of the conjecture holds for planar graphs withΔ≥10.

关键词： planar graphs neighbor sum distinguishing total choosibility combinatorial nullstellensatz discharging method

Investigating the effect of volatility on the hygroscopicities of acetate nanoparticle aerosols by surface plasmon resonance microscopy

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Journal of Environmental Sciences 2024年第4期138卷 167-178页

作者： Bo Yang Zhibo Xie Jianguo Liu Huaqiao gui jiaoshi zhang Xiuli Wei Zetao Fan Douguo zhang Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China CAS Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Advanced Laser Technology Laboratory of Anhui Province Department of Optics and Optical EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Under high relative humidity(RH)conditions,the release of volatile components(such as acetate)has a significant impact on the aerosol hygroscopicity.In this work,one surface plasmon resonance microscopy(SPRM)measurement system was introduced to determine the hygroscopic growth factors(GFs)of three acetate aerosols separately or mixed with glucose at different RHs.For Ca(CH_(3)COO)_(2) or Mg(CH_(3)COO)_(2) aerosols,the hygroscopic growth trend of each time was lower than that of the previous time in three cyclic humidification from 70% RH to 90% RH,which may be due to the volatility of acetic acid leading to the formation of insoluble hydroxide(Ca(OH)_(2) or Mg(OH)_(2))under high RH conditions.Then the third calculated GF(using the Zdanovskii-Stokes-Robinson method)for Ca(CH_(3)COO)_(2) or Mg(CH_(3)COO)_(2) in bicomponent aerosols with 1:1 mass ratio were 3.20% or 5.33% lower than that of the first calculated GF at 90% RH.The calculated results also showed that the hygroscopicity change of bicomponent aerosol was negatively correlated with glucose content,especially when the mass ratio of Mg(CH_(3)COO)_(2) to glucose was 1:2,the GF at 90% RH only decreased by4.67% after three cyclic humidification.Inductively coupled plasma atomic emission spectrum(ICP-AES)based measurements also indicated that the changes of Mg^(2+)concentration in bicomponent was lower than that of the single-component.The results of this study reveal thatduring the efflorescence transitions of atmospheric nanoparticles,the organic acids diffusion rate may be inhibited by the coating effect of neutral organic components,and the particles aging cycle will be prolonged.

关键词： Hygroscopic growth Volatility Acetate aerosols Nanoparticle aerosol Surface plasmon resonance

Contrastive Consistency and Attentive Complementarity for Deep Multi-View Subspace Clustering

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Computers, Materials & Continua 2024年第4期79卷 143-160页

作者： jiao Wang Bin Wu Hongying zhang School of Information Engineering Southwest University of Science and TechnologyMianyang621010China

Deep multi-view subspace clustering (DMVSC) based on self-expression has attracted increasing attention dueto its outstanding performance and nonlinear application. However, most existing methods neglect that viewprivatemeaningless information or noise may interfere with the learning of self-expression, which may lead to thedegeneration of clustering performance. In this paper, we propose a novel framework of Contrastive Consistencyand Attentive Complementarity (CCAC) for DMVsSC. CCAC aligns all the self-expressions of multiple viewsand fuses them based on their discrimination, so that it can effectively explore consistent and complementaryinformation for achieving precise clustering. Specifically, the view-specific self-expression is learned by a selfexpressionlayer embedded into the auto-encoder network for each view. To guarantee consistency across views andreduce the effect of view-private information or noise, we align all the view-specific self-expressions by contrastivelearning. The aligned self-expressions are assigned adaptive weights by channel attention mechanism according totheir discrimination. Then they are fused by convolution kernel to obtain consensus self-expression withmaximumcomplementarity ofmultiple views. Extensive experimental results on four benchmark datasets and one large-scaledataset of the CCAC method outperformother state-of-the-artmethods, demonstrating its clustering effectiveness.

关键词： Deep multi-view subspace clustering contrastive learning adaptive fusion self-expression learning

Study on the green extraction of corncob xylan by deep eutectic solvent

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Grain & Oil Science and Technology 2024年第1期7卷 50-59页

作者： Bingyu jiao Le Wang Haitao gui Zifu Ni Rong Du Yuansen Hu School of Biological Engineering National Engineering Research Center of Wheat and Corn Further ProcessingZhengzhou 450001China

Corn as one of the world's major food crops,its by-product corn cob is also rich in resources.However,the unreasonable utilization of corn cob often causes the environmental pollution,waste of resources and other problems.As one of the most abundant polymers in nature,xylan is widely used in food,medicine,materials and other fields.Corn cob is rich in xylan,which is an ideal raw material for extracting xylan.However,the intractable lignin is covalently linked to xylan,which increases the difficulty of xylan extraction.It has been reported that the deep eutectic solvent(DES)could preferentially dissolve lignin in biomass,thereby dissolving the xylan.Then,the xylan in the extract was separated by ethanol precipitation method.The xylan precipitate was obtained after centrifugation,while the supernatant was retained.The components of the supernatant after ethanol precipitation were separated by the rotary evaporator.The ethanol,water and DES were collected for the subsequent extraction of corn cob xylan.In this study,a novel way was provided for the green production of corn cob xylan.The DES was used to extract xylan from corn cob which was used as the raw material.The effects of solid-liquid ratio,reaction time,reaction temperature and water content of DES on the extraction rate of corn cob xylan were investigated by the single factor test.Furthermore,the orthogonal test was designed to optimize the xylan extraction process.The structure of corn cob xylan was analyzed and verified.The results showed that the optimum extraction conditions of corn cob xylan were as follows:the ratio of corn cob to DES was 1:15(g:mL),the extraction time was 3 h,the extraction temperature was 60℃,and the water content of DES was 70%.Under these conditions,the extraction rate of xylan was 16.46%.The extracted corn cob xylan was distinctive triple helix of polysaccharide,which was similar to the structure of commercially available xylan.Xylan was effectively and workably extracted from corn cob by the DES method.This study provided a new

关键词： Corncob Deep eutectic solvent Xylan Process optimization Extraction

Ginkgo Biloba Extract Ameliorates Scopolamine-induced Memory Deficits via Rescuing Synaptic Damage

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Current Medical Science 2022年第3期42卷 474-482页

作者： gui-jiao zhang Dong ZHENG Huan YU Xiao-ping LUO Wei WU Department of Pediatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Orthopedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Objective Alzheimer’s disease(AD)is the most common age-related neurodegenerative disorder.Emerging evidence suggests that synaptic dysfunction is associated with the onset and progression of AD.Interestingly,Ginkgo biloba extract(EGb)is one of the most frequently investigated herbal medicines for enhancing cognition and alleviating neurodegenerative dementia.This study aimed to investigate the effect and the mechanism of EGb on AD-like synaptic disorders.Methods Scopolamine(SCO)-induced rats were used to mimic AD-like memory deficits.Morris water maze test and fear conditioning test were conducted to evaluate the memory status of rats in response to different treatments.Then,the synapse alterations were assessed by Golgi staining,and Western blotting was conducted to assess the protein expression of PSD95,GluN2B,synapsin-1,and synaptophysin.Reverse transcription quantitative polymerase chain reaction was applied to detect the mRNA expression of PSD95 and the levels of miR-1-3p/miR-206-3p.Results EGb supplement alleviated the learning and memory deficits induced by SCO in behavioral experiments.Moreover,EGb treatment attenuated synaptic damage elicited by SCO,manifested as increased dendritic spine density and the proportion of mushroom-type spines in hippocampal neurons.Further investigation indicated that EGb rescued the expression of synaptic-related proteins,especially PSD95,and decreased the levels of miR-1-3p/miR-206-3p in the rat hippocampus.Conclusion The application of EGb effectively treats SCO-induced memory impairments probably by suppressing miR-1-3p/miR-206-3p and elevating the expression of PSD95.

关键词： Ginkgo biloba extract Alzheimer’s disease synapse PSD95 MiR-1 MiR-206

Synthesis of a High-Efficiency Demulsifier and Study on Optimal Demulsification Conditions

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 107-115页

作者： Zhu Shuai zhang YingYu gui Xia College of Chemical Engineering Nanjing Tech University30 Puzhunan RoadNanjing 211816China

Oil and water separation has always been a top priority in the oil industry.In this study,a series of hyperbranched fluorinated polyamine-amine polymers(HFPA1-5)were synthesized directly using an improved“one-pot method.”The highly active fluorinated p-trifluoromethylaniline was used as the core raw material,while diethylenetriamine and methyl acrylate were used as the chain segment.A hyperbranched fluorine-containing polyamine-amine demulsifier(NHFPA6)was obtained through nano-grafting copolymerization of HFPA5.To enhance the demulsification and dehydration performance,the copolymerized HFPA6 was modified and combined.Then,the effects of the combination ratio,demulsifier concentration,demulsification time,and demulsification temperature on the demulsification effect were investigated.The results revealed that a combination ratio of DE-401:NHFPA6=1:1,a demulsification temperature of 50℃,a demulsification time of 60 min,and a demulsifier concentration of 150 mg/L yielded a dehydration rate as high as 99.80%.A response surface optimization design of demulsification conditions was performed.The model verified that the optimal demulsification conditions were 50℃,300 mg/L,and 90 min.However,considering the economic benefits of factories,it is more favorable to select demulsification conditions with a shorter time and lower concentration when the dehydration standard is met.Therefore,the demulsification conditions were selected as 50℃,150 mg/L,and 60 min.Compared to existing demulsifiers,the demulsifier developed in this study exhibits a lower demulsification temperature and higher demulsification efficiency.

关键词： hyperbranched fluorinated polyamine-amine nano-SiO_(2)